Can a Resorbed Tooth Be Saved? Heithersay and Patel Evidence
A 2026 multicentre study of 296 teeth updates an earlier Heithersay-focused review: 3D lesion extent was associated with tooth survival, but neither system guarantees an individual outcome.
External cervical resorption (ECR) can progress without pain as tooth structure is lost near the gumline. Once found, the question is whether the affected tooth can remain functional and restorable. Classification helps describe the lesion, but no class guarantees an individual's result.
Two ways to describe a lesion
The Heithersay system (Classes I–IV) describes the depth of ECR on conventional imaging. The Patel system uses CBCT 3D imaging to describe height, how far the lesion wraps around the root, and its relationship to the canal. The systems capture different information; both can inform discussion, not replace examination and planning.
How the 2026 evidence changed the interpretation
A 2026 narrative review by Rossi-Fedele and colleagues summarized earlier studies linking lower Heithersay classes with better outcomes. At the time it found insufficient evidence to establish the prognostic value of Patel's 3D system. That was a summary of the literature then available, not proof that Heithersay was always the stronger predictor.
A later multicentre retrospective cohort by Patel and colleagues, first published online June 4, 2026 (September issue of the International Endodontic Journal), followed 296 teeth in 233 patients across five specialist practices. Mean follow-up was 2.9 years (range 12–123 months). Greater Patel 3D lesion extent, particularly circumferential involvement over 180°, was associated with a higher extraction hazard. Heithersay class was not significantly associated with survival in this cohort. This does not erase older studies, but it does overturn a blanket claim that Heithersay is more useful than Patel for predicting survival.
What do the survival numbers mean?
Kaplan–Meier estimated tooth survival was 95.5% at 1 year, 93.3% at 2 years, 85.7% at 5 years, and 80.5% at both 7 and 10 years. Survival means the tooth had not been extracted; it is not the same as treatment success (being asymptomatic and healed). Longer-term estimates should not be read as a promise for a particular tooth.
In the same cohort, estimated cumulative survival was 93.6% for selected teeth monitored without immediate repair, 90.2% for external repair and 59.1% for internal repair. These groups were not interchangeable: treatment depended on lesion accessibility, symptoms and other clinical features. The figures cannot show that observation is superior to repair or that one approach caused the differences. Do not use the group percentages to choose a treatment without a case-specific assessment.
What early detection can and cannot do
A small lesion found early may leave more treatment options, but it does not guarantee that a tooth can be saved. A lesion's 3D circumference, accessibility, symptoms, reparative activity and remaining tooth structure matter. A pink spot or suspicious X-ray finding merits timely assessment; the appropriate choice may be monitoring, external repair, internal repair or extraction depending on the case.
Clinical interpretation approved by Dr. Jason Kung
“I assess the three-dimensional extent of resorption, its accessibility, the tooth's restorability and the patient's symptoms together. A classification or study survival percentage alone cannot determine whether an individual tooth should be repaired, monitored or removed.”
Dr. Kung approved this clinical interpretation only; the full article remains pending medical review.
For further reading, see the earlier narrative review and the newer cohort. This research interpretation is an editorial update based on published evidence; the article as a whole remains pending medical review. For an individual assessment, see our tooth resorption guide or contact the office.